Accidentally Searched For a “Rock Tumblr”

“Basically, there are two ways you can go about buying a rock tumbler. You can pick up the standard educational-toy model online or at most toy stores or you can get a hobbyist/professional model. Which to choose? Anything to watch out for? Preparations to make? Read on…”
—Are YOU ready to rock (tumble)!? Once you get them all shiny, what will you do with them? Put them in this.